• 멤브레인
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• 제23권6호
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• pp.469-474
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• 2013

알칼리 수전해용 격막으로 사용하기 위해 음이온교환막을 제작하였다. 음이온교환막은 PVC (polyvinyl chloride)를 출발물질로 하여 클로로메틸화 및 아민화에 의해 제작하였다. 제작한 막은 막 특성(막 저항, 이온교환용량)을 평가하였다. 제작한 음이온교환막의 1M NaOH수용액에서의 최저 막 저항은 $2.9{\Omega}{\cdot}cm^2$를 나타냈다. 이 막은 2.17 meq./g-dry-membrane의 이온교환용량과 43.4%의 함수율을 보였다. 제작한 음이온교환막의 막 특성을 시판의 막 특성과 비교 평가하였다. 1M NaOH수용액에서의 막 저항은 AHT>IOMAC>Homemade membrane>AHA>APS=AFN의 순으로 저항 값이 높았다. 이온교환 용량은 Homemade membrane>AFN>APS>AHT>AHA>IOMAC의 순으로 높은 값을 가졌다.

• 동아시아경상학회지
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• 제6권3호
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• pp.24-36
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• 2018

Purpose - From establishing China-Japan diplomatic relations in 1972, the relations between two states has improved a lot, from which makes the government and the people reap much benefit. Owing to this reason, this paper aims at exploiting the impact of exchange rate volatility of RMB on China's foreign direct investment to Japan. Research design and methodology - The quarterly time series data from 2003 to 2016 will be employed to conduct an empirical analysis under the vector error correction model. Meanwhile, a menu of estimated methods such the Johansen co-integration test and the Granger Causality test will be also used to explore the impact of exchange rate volatility of RMB on China's foreign direct investment to Japan. Results - The empirical analysis results exhibit that the real exchange rate has a positive effect on China's foreign direct investment to Japan in the long run. Conversely, the real exchange rate volatility of RMB, the trade openness and the real GDP have a negative effect on China's foreign direct investment to Japan in the long run. However, in the short run, the China's foreign direct investment to Japan, the real exchange rate, the trade openness and the real GDP in period have a negative effect on China's foreign direct investment to Japan in period. Oppositely, the real exchange rate volatility of RMB in period has a positive effect on China's foreign direct investment to Japan in period. Conclusions - From the empirical evidences in this paper provided, it can be concluded that an increase in the exchange rate volatility of RMB can result in a decrease in the China's foreign direct investment to Japan in the long run. However, an increase in the exchange rate volatility of RMB can lead to an increase in the China's foreign direct investment to Japan in the short run. Therefore, the China's government should have a best control of the real exchange rate volatility of RMB so as to improve China's foreign direct investment to Japan.

• 대한영양사협회학술지
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• 제7권1호
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• pp.9-18
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• 2001

Dietitians in various fields have used food exchange lists for food preparations. However it seems that the present food exchange lists are complicated, thus they cause many problems for dietitians to use in the fields. Therefore this study evaluated to the extent of awareness and utilizations of KDA food exchange lists in dietitians and also collected dietitian's opinions for revising food exchange lists such as serving size, serving calories, and for unifying food guidelines and dietary and dietary guidelines for Korean to one simple guideline. 192 dietitians who presently work in urban and rural areas were recruited and data based on survey were collected. As results, most of dietitians(87.5%) knew well about food exchange lists, but only 7.8% of them always would use food exchange lists for menu planning, 56.3% of dietitians did not use it at all and 34.4% occasionally use it. And 88.0% of dietitians wanted to revise food exchange lists totally or partially, 69.8% of dietitians hoped to amend various calories per one serving in food exchange lists to one serving calorie. The desirable on serving calorie was selected as 100kcal(51%) or 50kcal(38%) by dietitians. The dietitians in this study understood very well dietary guidelines(86.5%) and food guidelines(88.5%) for Korean, and 66.1% dietitians wanted to unify both guidelines. In case of unification of guidelines, dietitians answered that 7-8 items(30%) or 5-6 items(27%) should be included in guideline. In the question about reference value for daily allowance, most dietitians(56%) satisfied with the present various reference values for various generation while 28% of dietitians wanted to change to have one reference value (standard with 2000kcal, adult female). This study will provide basic informations for revising or adjustment of food exchange list and dietary or food guidelines for Korean.

• 폴리머
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• 제31권4호
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• pp.315-321
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• 2007

본 연구에서는 방사선 중합방법으로 아민화 PONF-g-GMA 이온교환 섬유를 합성하였다. 또한 핫멜트 web spray 접착방식으로 이들과 비드 수지를 결합시켜 복합 이온교환 섬유를 제조하고 이들의 바나듐 흡착특성을 확인하였다. 복합 이온교환 섬유의 이온교환 용량은 비드보다는 낮았으며, 단일 이온교환 섬유보다는 높게 나타났으며 최대 4.18 meq/g로 나타났다. 또한, 복합 이온교환 섬유의 바나듐 흡착 파과평형은 550분으로 비드 이온교환 수지보다 빠르게 진행되었고, 섬유상 이온교환체보다는 느리게 진행되었다. 한편, 바나듐의 흡착파과 시간은 pH가 낮아짐에 따라 파과가 빠르게 진행되었으며, 바나듐 농도가 증가함에 따라 흡착 평형에 도달하는 시간은 400분 전후에서 나타났다.

• Journal of Advanced Marine Engineering and Technology
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• 제27권6호
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• pp.797-805
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• 2003

This paper describes experimental investigations of helium-air exchange flow through single opening and partitioned opening. Such exchange flows may occur following rupture accident of stand pipe in high temperature gas cooled reactor. A test vessel with a small opening on top of test cylinder is used for experiments. An estimation method of mass increment is developed and applied to measure the exchange flow rate. A technique of flow visualization by Mach-Zehnder interferometer is provided to recognize the exchange flows. Flow measurements are made with the opening, for partition ratios H_p/H$_1$$ in the range 0 to 1. where H_p$ and H$_1$ are partition length and height of the opening. respectively. In the case of H_p/H$_1$$ of 0, flow passages of upward flow of the helium and downward flow of the air within the opening are unseparated (bidirectional), and the two flows interfere within the opening. The unseparated flow increases strength of flow resistance and therefore, the exchange flow rate is minimum through range of the partition ratios. Two flow zones, i.e., separated (unidirectional) flow zone and unseparated (bidirectional) flow zone, exist with increasing the partition length. The exchange flow rate increases with increasing the separated flow zone. It is found that a maximum exchange flow rate exists at H_p/H$_1$$ of 1. As a result of comparison of the exchange flow rates by changing the partition ratio, the fluids Interference in the unseparated zone is found to be an important factor on the helium-air exchange flow rate.

• 한국산학기술학회논문지
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• 제7권4호
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• pp.727-732
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• 2006

본 연구에서는 전해질 성분 및 농도, 이온교환 수지 조성비율을 통해 이온교환 수지탑의 성능을 평가하고, 이온교환 수지에 의한 입자성 물질 제거의 능력과 입자성 물질이 이온교환 특성에 미치는 영향을 조사하였다. 이온교환 수지탑 배열 순서에 따라 파과(돌파)시점이 연장되며, 파과(돌파)순서는 음이온의 경우 $Cl^{-}, 양이온의 경우 $Na^{+} 순 이였으며, 전해질의 농도가 증가할수록 파과시간이 단축되었다. 이온교환 수지의 조성비 변화에서는 양음이온교환 수지 조성비가 1:2의 경우 1:1및 1:3의 경우보다 파과(돌파)시간이 연장되었으며 동일한 전해질 농도에서 입자 농도가 증가하면 20% 미만으로 파과(돌파)시간이 단축되었다. 양이온 교환수지 비율이 높으면 양이온의 파과(돌파)시점이 늦어져 이온교환 수지탑의 수명이 연장되고, 입자성 물질은 전해질 농도와 무관하게 이온교환 수지의 세공을 막아 이온교환 용량을 감소시켜 파과(돌파)시간을 단축시키는 것으로 조사되었다.

• Geomechanics and Engineering
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• 제14권3호
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• pp.283-291
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• 2018

Cracks in soil provide significant preferential pathways for contaminant transport and rainfall infiltration. Water exchange between the soil matrix and crack is crucial to characterize the preferential flow, which is often quantitatively described by a water exchange ratio. The water exchange ratio is defined as the amount of water flowing from the crack into the clay matrix per unit time. Most of the previous studies on the water exchange ratio mainly focused on cracked sandy soils. The water exchange between cracks and clay matrix were rarely studied mainly due to two reasons: (1) Cracks open upon drying and close upon wetting. The deformable cracks lead to a dynamic change in the water exchange ratio. (2) The aperture of desiccation crack in clay is narrow (generally 0.5 mm to 5 mm) which is difficult to model in experiments. This study will investigate the water exchange between a deformable crack and the clay matrix using a newly developed experimental apparatus. An artificial crack with small aperture was first fabricated in clay without disturbing the clay matrix. Water content sensors and suction sensors were instrumented at different places of the cracked clay to monitor the water content and suction changes. Results showed that the water exchange ratio was relatively large at the initial stage and decreased with the increasing water content in clay matrix. The water exchange ratio increased with increasing crack apertures and approached the largest value when the clay was compacted at the water content to the optimal water content. The effective hydraulic conductivity of the crack-clay matrix interface was about one order of magnitude larger than that of saturated soil matrix.

• KDI Journal of Economic Policy
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• 제28권1호
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• pp.193-218
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• 2006

본 논문은 한국의 근본적인 거시경제변수가 두 가지 다른 환율제도(자유변동 환율제도와 시장평균 환율제도)하에서 어떻게 다르게 반응하는가를 분석 연구한다. 이와 아울러 같은 기간 동안의 일본과 호주의 거시경제구조에 대한 비교 분석도 곁들인다. 한국은 1997년의 경제위기를 전후하여 환율정책을 시장평균 환율제도에서 자유변동 환율제도로 전환하였다. 이 시점을 계기로 한 한국의 외환정책 변경은 두 가지 환율제도를 비교 분석하는 데 아주 좋은 기회를 제공한다. 화폐경제이론에 기초한 환율결정 모델을 사용하여 대미환율과 거시경제변수에 대한 관계를 분석해 본 결과, 대미환율은 시장평균 환율제도하에서보다 자유변동 환율제도하에서 근본적인 거시경제변수에 더 민감하게 반응하는 것으로 나타났다. Impulse Response Analysis 분석결과에 의하면, 환율변동이 물가상승률에 미치는 영향은 시장평균 환율제도하에서 보다 자유변동 환율제도하에서 단기적으로 더 큰 것으로 나타났다. 이러한 결론은 개발도상국가에서는 안정적인 관리 환율제도가 경제성장을 위해 필요하다는 일반적인 견해와 일치하는 것이다.

• 아태비즈니스연구
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• 제8권2호
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• pp.31-39
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• 2017

Countries around the world have been engaging in automatic exchange of information to tackle tax evasion. The same goal became the basis of the enactment of the Foreign Account Tax Compliance Act (FATCA) by the United States Congress. In order to establish a common approach to counter tax evasion among different countries, the Organization of Economic Cooperation and Development (OECD) released the Standard for Automatic Exchange of Financial Account Information in Tax Matters which consists of the Competent Authority Agreement (CAA) and the Common Reporting Standard (CRS). Specifically, the automatic exchange of information is the exchange of financial account information between Tax Authorities in relevant countries. The law requires this information to be collected by financial institutions around the world for reporting to Tax Authorities. Automatic exchange of Information is made up of two information sharing frameworks: The Foreign Account Tax Compliance Act (FATCA) and The Common Reporting Standard (CRS). Under the automatic exchange of information, all financial institutions must identify accounts held by customers who are foreign tax residents or entities connected to foreign tax residents. Financial institutions must report these to the relevant Tax Authority who will then automatically exchange the account information with the relevant foreign Tax Authorities. Korean government has enacted domestic laws to require financial institutions to collect and report this information and has entered into international agreements to exchange the information with other governments. This paper analyzed the FATCA and CRS rules overall and proposed solutions for the legal and practical issues. This paper contributes to the existing literature on the automatic exchange of information by considering two information sharing frameworks.

• Journal of Advanced Marine Engineering and Technology
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• 제23권2호
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• pp.192-200
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• 1999

This paper describes experimental investigations of helium-air exchange flow through parti-tioned opening. Such exchange flow may occur following rupture accident of stand pipe in high temperature gas cooled reactor. A test vessel with a opening on top of test cylinder is used for experiments. An estimation method of mass increment is developed and applied to measure the exchange flow rate. A technique of flow visualization by Mach-Zehnder interferometer is provided to recognize the exchange flows. Flow measurements are made with partitioned opening for parti-tion rations $H_p/H_1$ in the range 0 to 1 where $H_p$ and $H_1$ are partition length and height of the open-ing respecticely. In the case of $H_p/H_1$ of 0 flow passages of upward flow of the helium and down-ward flow of the air within the opening are unseparated (bidirectional) and the two flows interact exchange flow rate is minimum through range of the partition ratios, Two flow zones i.e. separat-ed(unidirectional)flow zone and unseparated(bidirectional) flow zone exist with increasing the partition. length, The exchange flow rate increases with increasing the separated flow zone. It is found that a maximum exchange flow rate exists at $H_p/H_1$ of 1. As a result fo comparison of the exchange flow rates by changing the partition ration the fluids interaction in the unseparated zone is found to be an important factor on the helium-air exchange flow rate.